In general, in a general-purpose computer system such as a work station and a personal computer, a specific-purpose computer system such as a vehicle navigation device, a micro computer suitably used for an audio system and an air conditioner, operation information with respect to all of information processing devices is input with using information input elements such as a key board, a mouse and a button.
Recently, the operation information is input by gestures, i.e., movement of a body of a user. For example, a method for inputting the operation information with using a finger movement, which provides a wide variety of motions, is described in JP-A-2008-276664 and JP-A-2002-358149 corresponding to US 2004/0243342.
JP-A-2008-276664 teaches a technique that a Piezo electric sensor with a cable shape having flexibility is attached to a finger of a user so that the sensor detects a bending motion and a stretching motion of the finger. Then, the detection result is used for operation information.
JP-A-2002-358149 teaches an information input device formed to be a wristwatch type device so that the information input device is worn on a wrist of the user. With using a transmission electrode and a reception electrode alternately arranged around the wrist in a circumferential direction, a motion of an arm and a hand (i.e., an upper extremity) of the user is detected. Specifically, an electro-static coupling generated between a transmission electrode and an adjacent reception electrode is changed with a gap between these electrodes and the wrist. When the user moves the arm and/or hand, the shape of the arm and/or hand is slightly changed according to the movement of the arm and/or hand. Thus, the gap between the electrodes and the wrist is changed, so that the electro-static coupling value is changed. When the change of the electro-static coupling value is detected, the movement of the hand and arm is detected.
Thus, the motion of the upper extremity, i.e., the gesture is detected. A specific gesture such as grasping movement of the hand and opening movement of the hand connects with the operation information as an input command, which is to be input into the information processing device. The relationship between the gesture and the input command is stored, so that the operation information is input into the information processing device according to the gesture.
However, the detection method with using the Piezo sensor having flexibility and attached along with the finger requires to wear the sensor on the finger. Thus, similar to a data globe, a step for wearing the sensor on the finger is bothersome. When the attachment of the sensor is bothersome, the user feels physical strain such that the user wears the Piezo sensor on the finger, and mental strain such that the user has to attach and detach the sensor on the finger.
The information input device described in JP-A-2002-358149 detects the motion of the upper extremity based on the change of the shape of the upper extremity. Thus, the device can detect the gesture, which provides a big change of the shape of the upper extremity. However, the device can not detect the gesture, which provides a small change of the shape of the upper extremity.